Wrench



F. R. GILBY.

WRENCH.

APPLICATION FILED MAILS. IszI.

Patented July 4, 1922?.

FRANK R. GILBY, OF DETROT, MICHIGAN.

WRENCH.

hiciese.

Specification of Letters Patent.

Application filed March 5, 1921. SeralrNo. 449,724.

j To all whom t may concern."

Be it known that FRANK R. GILBY, a

@tate of Michigan, have invented certain new and useful improvements 'in l/Vrenches, of which the following is a specification, reference being had therein tothe accompanying drawings.

.This invention relates to an improvement in the form of wrench commonly known as a monkey wrench7 and it has for its object the provision of a gripping dog which n ormally will be held in .a position in which 'the opposed parallel faces of theV ixed and movable jaws will be left smooth, `lout which may be moved into position to grip a cylin-v drical rod or a pipe when needed. A further object of my invention isto provide a latchV which will hold the grip- Y ping dog securely in inoperative position,

and which will alsoact'asV a means to hold ,the dogresiliently in its operative position.

VVit-h the above primary and other incidental objects in View as will more fully appear in the specification, the invention, consists in the features of construct-ion, the parts i and combinations thereof, and the inode of operation, or,` their equivalents as hereinafterl Vdescribed and set forth in the claims.

i In `the drawing, .j

Figure 1 is a view in elevation of a mon- .;key. wrench, the end portion being in section and the dog'being in inoperative posi-v tion;V

(Fig. 2 isl a similar view showing the dog in operative position,

,'Fig. 3 is an end view partly in section;

Fig. 4 is a fragmentary sectional viewv showing a modified form of securing means r for the Ylatchin device; and 'Y Fig. v5 is an e evation of a modification in` whichthe dogi'is secured in the movable jaw.

In Fig.' 1, the shank 10 is shown ofva conventional form with the usual rack 11 engaged by the screw 12 for the purpose of adjusting the movable jaw 13 as is familiar in the art. The iixed jaw 14 is formed inte" gral with the shank'lO and is longitudinally slotted at 15 to receive tang 16 of a pivoted dog having one edge formed with a smooth Vsurface 17, the inner part of which, when -the dog is` in its inoperative position, lies Hush with-the inner fac-e 18 of the jaw 14. The outer part of the dog forms an extenl sion of the aw. lThe outei face of the pivoted' dog is preferably formed as the are vvserrations for a purpose which willhereinafter be described. In the edge Aof the tang 16 adjacent tothe shank 10v is Vformed a notch 20, one side of which has a cam surface 21 arranged to be engaged by the end of a pin 22. The pin 22 is normally` held in engagement with the tang by means of a spring 23 engaging an abutment 24,- shown in the present instance as a collar, on Athe pin 22.r The other end of the spring bears against a bushing 25 threaded linto al bore in the shank 1() in theform shown in Fig. 1. An alternative'arrangement is shown in Fig. 4in which a sleeve 26 is held in the borein the shank bya transverse pin 27. A suitable head-28 ineither formV may be used as a convenient means for withdrawing the pin 22 from engagement with the tang to permit pivotal 4movement of the dog. The shank 10 ispreferably recessed at 29 so that the head 28 will not project beyond the surface of the shank 10.

lt will be apparentin Fig. 1 that theain rangement of the cani surface 21 is such that the pressure upon it of the rounded end of the pin 22 will tend to rotate the pivcontact with the shank of the wrench and that in this position the lower face in Fig. 1 will be flush with the inner face 18 of the yfixed jaw 14.

. The operator may clasp the head 28 of the pin 22 and withdraw the pin from'the notch p 20. rlhe pivoted dog will then be free to swing on the pivot 19 into the position shown in Fig. 2. When the'head 28 is released, the spring 28 will thrust the end `of the pin 22 againstthe face'l? of the tang 16, and since the axis of the pin lies above the pivot 19, in Fig. 2, the pressure of the spring will cause the pivoted dogto be held yieldably within the space betweenl the fixed jaw 14 and the movableV jaw 13. lf a pipe 30 or other cylindrical object is engagedbetween the j a'w 13 and the pivoted dog and the mov able jaw is adjusted 'in conformity with the diameter of the pipe or other object, the serrations 31 on the arcuate 'face of the pivoted dog will engage the surface of the object 30 and when the shank 10 is rotated Patented .iuiy 4, 1922.

counterclockwise, as indicated by the arrow in F ig. 2 beneath the movable jaw 13, the

serrations 31 will tend to imbed themselves fthe object slips, it will strike againstthe surface of the dog with respect to the pivot' ,shank between the jaws.

'In practice, Ifind that by providinga lsmall rounded notch 32 in the face of Ythe jawd, I am enabled to grasp very small in the fixed j aw 141:, it is obvious that it could be placed in the movable jaw 13 as shown in 5,, the operation being, of course, the

,same` in either case.

In practice the eccentricity of the' curved 19 may bevaried within certain limits, but I have found the gripping action to be best when the Center of the pivot 19 lies at a distance from the center of curvature of the Curved face of the dog equal to about nine sixteenths of the radius. The distance from the center of the kpivot to the gripping surface lof the dog increases toward the shank, or inward'of the space between the jaws, land the distance at any chosen point of .the Vgripping surfacefrom the pivot is greaterthanlthe `distance from the lpivot to. aline parallel `tothe face'of the opposing jaw, and passing through the vchosen pointf ,From the. above description, it will be apparent that there is thus provided a de- .i vice of the Vcharacter described possessing the particular features of advantage before enumerated as desirable, but which obviously 4 is susceptible of modification in its form,

proportion, detail constructionand arrange- ,rneIt 0f parts without departure from the principle'involved or sacrificing any of its advantages.

Y. i f While in order to comply with the statute f the invention has been described in language more or less specific as to`` structural features, it is to be understood that the in- Y vention is not limited to the specific details shown, but that the means and construction herein disclosed comprise but one of several modes of putting the invention into effect, `and the invention is therefore claimed in any of its forms or modifications witliin'the Y .legitimate valid scope of the'appended t Claims! I claim 1.v A wrench having a dog `pivoted there- Vin the foregoing description thel 4pivoted dog has been described as located on, a shank, anda jaw, the dog having a curved serrated surface eccentric to theV pivot, the radial distance of the eccentricV surface from'the pivot being greatest adjacent to the shank whereby movement of the dog away from the shank causes'the serrated surface to approach the jaw.

2. A wrench' having opposed fixed and Vmovable jaws, a shank, a dog having a convexly curved serrated surface pivoted ,upon one of the jaws, upon a pivot eccen- 3. In a wrench having a` fixed jaw and i a movable jaw having opposed smoothfaces, an adjustable dog having a smooth surface and aserrated surface and so mounted upon one of the jaws, that in one position of adjustment, the smooth surface of the dog lies substantially iiushV with the smooth face of the jaw,V and in another position of adjustment, the serrated surface of the dog lies opposite to the smooth face of the 'other jaw. i t. A wrench as` in claim 3, Ywherein a spring pressed latch is mounted in position to engage a portion ofthe pivoted .dog to hold it at one limit of pivotal movementand Y to engage another portion of the `dogrto hold it yieldably atV its opposite limit :of pivotal movement. Y jfr combination monkey wrench and pipe wreuchhaving a fixed aw and a mov loo n able jaw and' a dog pivoted in one of the jaws having a straight smoothsurface and a cam serrated surface, the pivotal mount ing of the dog being such, that-in one position of adjustment ofthe pivoted dog, Ythe straight smooth surface lies partly iushwith the surface of the jaw to which it'ispivoted and partly forms an extension kof 'the jaw and'in anotherv position'of'pivotaladjustment, the cam serratedsurface cfg-the dog lies within the space between the jawsf :6. A wrench as in claim 5, *whereinV the pivoted dog has a second cam surface engaged by aA spring held latch, to hold it rigidly in the positionVV of adjustment in which its straight surface is flush with the surface of thejaw. l Y Y -Y 7. A wrench as in claimrpwherein a resiliently held member engages theh smooth face of the Vdog to hold the serrated surface yieldingly in operativefposition between the aws. i Y

8. A wrenchhaving opposed jaws having substantially parallel faces,`a` shank, Vand a dog mounted upon yone of saidv jaws for Y vgripping movementin Vthe space between movement of the dog being such, that during its gripping movement away from said shank the distance from its surface to the surface of the opposed jaw becomes less.

9. A wrench having opposed jaws with substantially parallel faces, a dog pivoted to one of the jaws and having a curved gripping face eccentric to the pivot of the dog, the portion of the gripping surface most remote from the pivot lying inward of the space between the aws whereby outward pivotal movement of the dog will cause the distance from its gripping surface to the face of the opposed jaw to become less.

10. A wrench having opposed jaws, hav-n ing substantially parallel faces, and a dog mounted upon a pivot for movement in the space between the jaws, the dog having a gripping face on the side remote from the pivot, the distance of the gripping face from the pivot increasing on one side of the perpendicular drawn from the center of the FRANK R. GILBY.

Witnesses:

ANNA M. Dom, ARTHUR MINNICK. 

